Swiss Alps:
The effect of precipitation increase (especially since 1978) during the mild winters (since 1988) on often unfrozen and with low snow cover grounds, at altitude between 1000m and 1500m a.s.l contribute to an important modification of the hydrological cycle in Eastern Switzerland. With the freezing/defreezing cycles increase during winter, the efficacy infiltration increased strongly during the period between November and March and lead to an early saturation of the flysch are, with limited permeability during spring.

The precipitation and minimum temperature increase during winter is an aggrieving factor, with a direct effect on the water table level on surface and the water content of the unconsolidated materials in the Pre Alpine slopes under 1500 m a.s.l.

GCM output is postprocessed with a statistical downscaling technique to derive local-scale climate change information from simulated atmospheric circulation patterns. The resulting precipitation and temperature series are introduced in a hydrological tank model, which calculates daily groundwater levels.

Swiss Alps:
The 0°C isotherm altitude during winter is preponderant for the water table reload in the landslides located in the Pre Alps flysch area.

The winter precipitation increase (more than 20%), in form of rain or snow would have direct effect on the ground water content and on the water table surface. During mild winters, these precipitations may infiltrate more easily in the unfrozen grounds. The period of efficient infiltration may increase of 30 to 50 days for altitude between 1000 m and 1500 m a.s.l.